Do wild raccoons (Procyon lotor) use tools?

Animal Cognition - Being able to make and use tools was once considered to be an evolutionary hallmark of our species, but has since been documented in other animals. However, for reasons that...     

MEMORY WALLET INTERVENTION IN AN ADULT DAY-CARE SETTING

The use of memory wallets to prompt factual information during conversations with day-care center volunteers was evaluated for four subjects with dementia. Memory wallets contained 15–20 pictures and sentences about familiar persons, places, and events that each subject had difficulty remembering. All subjects used the memory wallets to improve their conversations by increasing factual statements and decreasing ambiguous, unintelligible, and perseverative utterances. Volunteers decreased their use of questions and prompts during conversations in which subjects used their memory wallets. These results demonstrate the effectiveness of using volunteers to develop memory wallets and to encourage their use during conversations with day-care clients.     

Is Every Theory of Knowledge False?

Is knowledge consistent with literally any credence in the relevant proposition, including credence 0? Of course not. But is credence 0 the only credence in p that entails that you don't know that p? Knowledge entails belief (most epistemologists think), and it's impossible to believe that p while having credence 0 in p. Is it true that, for every value of ‘x,’ if it's impossible to know that p while having credence x in p, this is simply because it's impossible to believe that p while having credence x in p? If so, is it possible to believe that p while having (say) credence 0.4 in p? These questions aren't standard epistemological fare—at least in part because many epistemologists think their answers are obvious—but they have unanticipated consequences for epistemology. Let ‘improbabilism’ name the thesis that it's possible to know that p while having a credence in p below 0.5. Improbabilism will strike many epistemologists as absurd, but careful reflection on these questions reveals that, if improbabilism is false, then all of the most plausible theories of knowledge are also false. Or so I shall argue in this paper. Since improbabilism is widely rejected by epistemologists (at least implicitly), this paper reveals a tension between all of the most plausible theories of knowledge and a widespread assumption in epistemology.     

Permissive Situations and Direct Doxastic Control

According to what I will call ‘the disanalogy thesis,’ beliefs differ from actions in at least the following important way: while cognitively healthy people often exhibit direct control over their actions, there is no possible scenario where a cognitively healthy person exhibits direct control over her beliefs. Recent arguments against the disanalogy thesis maintain that, if you find yourself in what I will call a ‘permissive situation’ with respect to p, then you can have direct control over whether you believe p, and you can do so without manifesting any cognitive defect. These arguments focus primarily on the idea that we can have direct doxastic control in permissive situations, but they provide insufficient reason for thinking that permissive situations are actually possible, since they pay inadequate attention to the following worries: permissive situations seem inconsistent with the uniqueness thesis, permissive situations seem inconsistent with natural thoughts about epistemic akrasia, and vagueness threatens even if we push these worries aside. In this paper I argue that, on the understanding of permissive situations that is most useful for evaluating the disanalogy thesis, permissive situations clearly are possible.     

What is presentism?

Presentism has received much scrutiny of late, yet little has been said of its definition. Many assume that it means simply that all that exists, exists at present. However, this definition will not do. It is defective in a multiplicity of ways. I consider and reject each of a number of intuitive ways in which to amend it. Each carries us a bit closer to our goal, but not until the end do we reach a definition that is wholly satisfactory. The final definition has this remarkable feature: it has us posit abstracta of two kinds, namely, times and haecceities.     

Situating social influence processes: dynamic, multidirectional flows of influence within social networks.

Social psychologists have studied the psychological processes involved in persuasion, conformity, and other forms of social influence, but they have rarely modeled the ways influence processes play out when multiple sources and multiple targets of influence interact over time. However, workers in other fields from sociology and economics to cognitive science and physics have recognized the importance of social influence and have developed models of influence flow in populations and groups-generally without relying on detailed social psychological findings. This article reviews models of social influence from a number of fields, categorizing them using four conceptual dimensions to delineate the universe of possible models. The goal is to encourage interdisciplinary collaborations to build models that incorporate the detailed, microlevel understanding of influence processes derived from focused laboratory studies but contextualized in ways that recognize how multidirectional, dynamic influences are situated in people's social networks and relationships.     

Early Adolescent Growth in Depression and Conduct Problem Symptoms as Predictors of Later Substance Use Impairment

Most studies of adolescent substance use and psychological comorbidity have examined the contributions of conduct problems and depressive symptoms measured only at particular points-in-time. Yet, during adolescence, risk factors such as conduct problems and depression exist within a developmental context, and vary over time. Though internalizing and comorbid pathways to substance use have been theorized (Hussong et al. Psychology of Addictive Behaviors 25:390-404, 2011), the degree to which developmental increases in depressive symptoms and conduct problems elevate risk for substance use impairment among adolescents, in either an additive or potentially a synergistic fashion, is unclear. Using a school-based sample of 521 adolescents, we tested additive and synergistic influences of changes in depressive symptoms and conduct problems from 6th to 9th grade using parallel process growth curve modeling with latent interactions in the prediction of late adolescent (12th grade) substance use impairment, while examining gender as a moderator. We found that the interaction between growth in depression and conduct disorder symptoms uniquely predicted later substance use problems, in addition to main effects of each, across boys and girls. Results indicated that adolescents whose parents reported increases in both depression and conduct disorder symptoms from 6th to 9th grade reported the most substance use-related impairment in 12th grade. The current study demonstrates that patterns of depression and conduct problems (e.g., growth vs. decreasing) are likely more important than the static levels at any particular point-in-time in relation to substance use risk.